LENSINK R (2017) Patterns in feeding and roosting of Great White Egret Ardea alba in the region Land van Maas en Waal, the Netherlands. LIMOSA 90 (4): 155-166.
In the riverine area in de centre of the Netherlands, a four
year study about the roosting and feeding behaviour of
Great White Egrets was conducted from July 2013 until April
2017. Weekly counts at three roosts revealed that the roost
in de flood plains along the Waal (Afferdensche & Deestsche
Waarden) showed a clear double peak of bird numbers
in late summer and early autumn, whereas the two inland
roosts (Batenburg, Ulandsestraat) had only a single peak in
winter. These differences were linked to a shift in feeding
habitat at the end of autumn, from aquatic feeding at the
food plains to terrestrial feeding on grassland. In winter,
the great majority of Great White Egrets is foraging on grassland,
where voles seem to form their main prey. Arrival at
the night roost shifted in the course of autumn in relation
to sunset, with birds arriving later in winter. On cloudy days
birds arrived earlier compared to clear days. In early autumn
juveniles (with no wing moult) could be distinguished easily
from adults (with wing moult). Most birds arrived solitary to
the night roost. Arrival in flocks was rare, and sometimes linked
to gatherings of feeding birds nearby of the night roost.
However, these pre-roosting gatherings could not be considered
pre-roosts as the birds would use them individually
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